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In one of my previous posts I talked about how roots grow up thru the weed barrier at the bottom of the SFG. I need something that will stop the roots from coming up thru, yet will allow what I have to drain. What would be the ramifications of putting solid plastic?

While not for everyone (requires a lot of work) we built our beds 29" tall, filled bottom 2/3rds with "vegetable mix" from a local vendor (if you are around the major metropolitan areas in Texas you probably know who I am talking about) this stuff was basically total crap (way too much wood left in it to be any use up front, I am sure it will be great in a year or two) we then custom blended (native soil, amendments, peat moss and a few other things) for the top 1/3.

To put it mildly we have had no issues with anything that was under these boxes growing up that high to penetrate the surface, we are very pleased with the boxes at this point as we do not even have to bend over to work on them and for me (6'4") that is a HUGE blessing. The deep rooting vegetables seem to be thoroughly enjoying it as well.

Lb, just a bit of back story for you, I think the previous thread that was mentioned was all about tree roots invading the bottom of the garden. That is why I am totally getting the 4 problem beds off the ground, the tree roots were choking the vegetables.Bud, I plan on just using plywood and drilling holes every 4"-6".When you say solid plastic, what is it that you are talking about? Plastic boards? Plastic film?

@Bud Alexis wrote:In one of my previous posts I talked about how roots grow up thru the weed barrier at the bottom of the SFG. I need something that will stop the roots from coming up thru, yet will allow what I have to drain. What would be the ramifications of putting solid plastic?

It comes to mind that a solid plastic say 1/6 inch thick with a platform of paving bricks on it would stop the problem and give your bed a good system of drainage especially if the plastic sheet & brick platform is 6 inches bigger all round than the ANSFG bed frame